In many industries including the pharmaceutical, food processing, chemical, plastics, cosmetics, mining and other industries, transport lines are utilized for pneumatically conveying bulk materials from one site to another. Typically, such lines consist of a number of conduits connected together in end-to-end relation, configured to provide a desired flow path of the material to be conveyed. Examples of systems utilizing such transport lines are illustrated and described in U.S. Pat. Nos. 6,609,871; 6,719,500; 6,722,822 and 6,764,253 which are incorporated herein by reference. Often, in order to avoid the growth of bacteria or insect infestation which could taint the product being handled, particularly in the pharmaceutical and food processing industries, it is required that such lines be cleaned regularly and thoroughly. Cleanliness also is required in applications where different types of material are handled by the same conveying line. An example of such application would be the handling of differently colored pigments where cross-contamination of color cannot be tolerated.
In conveying lines utilizing a number of such conduits arranged in end-to-end relation, usually connected together by clamps, bolts or other fastening means, in order to clean the interiors of such conduits, it is required to disassemble such conduits to obtain access to the interiors thereof and then reassemble them after cleaning which not only is labor intensive but time consuming, requiring the removal of the conveying line from production. In view of such shortcoming of existing conveying lines, it has been found to be desirable to provide a product conveying line made up of a number of conduit segments which may be cleaned while maintaining to a minimum the number of such segments that must be disassembled and then reassembled.